The answer to this question is yes for most UV cure coatings. The key will be the amount of process time it will take to complete the cure.

In terms of actual curing the wavelength of the UV lamp and the UV cure material will need to be compatible. This can be confirmed by checking the Technical Datasheet from the material supplier. Then it will be a question as to how much actual energy is needed to cure the coating. Again, this can be discussed with the material supplier.

SCH Technologies supply a high quality, cost-effective range of UV light curing equipment for batch and inline processing of electronics materials like adhesives and conformal coating.

This allows SCH to offer the complete UV cure solution regardless of the needs of the customer.

There are two types of UV meter that we are concerned with for conformal coating measurement. These are the UV Irradiance Meter and the UV Exposure Meter.

UV Irradiance Meter
The irradiance meter will give you a real-time read out of the “intensity” of the UV light. It reads in mW/cm2. It can be used for monitoring the drop off of UV light irradiance during the operating life of UV bulbs and tubes. It also can be used to determine the UV light transmission (%) of transparent materials such as glass, plastic and window tinting film. This in turn applies to checking comparative performance of UV blocking guards, screens, clothing and eye/face protection and leak checking of conformal coating process equipment like UV light cabinets, conveyors and systems

UV Exposure Meter
The exposure meter gives you an reading based on intensity and time. This reads in mJ/cm2. Generally the exposure meter is used for conveyer belts and fixed time exposures and ensures that the right energy is given to the conformal coatings and adhesives.

Its also possible to have both exposure and irradiance built into the same Meter. This gives you the best of both options.

As part of their continued growth into the conformal coating market SCH have introduced a new range of batch UV cure products. UV cure is fast becoming an important part of the conformal coating industry and to ensure that SCH meet the needs of the customers they have introduced several new products including:

UV cure conformal coatings cureswith UV radiation and therefore the material is almost instantly cured if the right light source is used.

The UV light you need for curing UV conformal coatings can be a mix of UVA, UVB and most importantly UVC. this will depend on the manufacturers formulation. However, the radiation can be dangerous if exposure is not controlled due to its high energy. Therefore, the UV light must be contained within a suitable system with safeguards against exposure. Conveyor UV cure ovens like the systems SCH offer are built to ensure exposure is avoided.

Other benefits beyond the fast cure are that UV cure coatings generally do not contain solvents or water within it meaning 100% of the product is coating and the product is classed solventless. Therefore, there are another two advantages. First, what you deposit when coating is what remains after curing. Second, you can reduce your solvent (VOC) emissions which can be important.

For instance, when you spray UV 40 it does not reduce in thickness like solvent and water based coatings, which are a blend of resin, chemicals and most importantly, the carrier solvent or water. You could spray a wet film thickness of 100 microns (0.1 mm) down and for solvent and water based coatings, the solvent and water “evaporate” leaving a thinner dry film thickness of approx 30-40 microns. The rest of the coating has volatised off into the atmosphere and is wasted. There is no evaporation with UV40 so if you coat 100 microns it dries 100 microns. Therefore, waste can be minimised.

Another important factor to consider for UV cured coatings are their secondary cure mechanism. This means that any coating not initially fully cured with the UV light will still continue to finish curing on it own. This is important because of shadowing effects which can be detrimental in curing. If you coat a PCB with a VU cure material some coating could get into areas where there is no way the UV light can get to it for curing. The coating is effectively in shadow from the UV radiation. The coating could then stay liquid which is not good (most coatings are conductive whilst wet and shorting on the PCB can occur where electricity can travel where it shouldn’t. Think of water and electricity. They don’t mix!). Therefore, a secondary cure mechanism is critical.

For many coatings, the secondary cure mechanism is moisture from the air causing the coating to cure. However, this is a much slower process and can take hours. This also means you need to handle the material carefully in storage and loading since exposing the coating to too much air can start the cure mechanism prematurely.

All these positive points mean for the high volume markets like the automotive industry this is a very important material with advantages such as speed of cure and no solvents.

Ultra-violet radiation forms part of the electromagnetic spectrum and is invisible to the naked eye. The wave length of UV radiation varies from 100-400nm, finishing in the blue portion of visible light.

In terms of energy output, the shorter the wavelength of the UV radiation the higher the energy of the light. These energy levels can be subdivided into 4 specific regions:

The IB100 conformal coating inspection booth is an ideal work station for operators to inspect & finish circuit boards which have been conformal coated.

Fitted with dual UVA lamps behind a safety screen to allow solvents to be used safely in the booth, the IB100 offers 36W of ultraviolet light for maximum visual inspection & finishing performance without compromise to operator safety in operation.

SCH have a dedicated training room for conformal coating courses and demonstrations of conformal coating equipment.

Using this facility candidates get complete hands-on experience with the conformal coating systems and processes without disturbance to production with a full range of systems available to ensure the best learning environment.

Whether you plan to install a conformal coating process or currently use conformal coatings such as Humiseal we can help to develop or optimise your conformal coating process, to ensure you achieve the best performance. SCH can offer expert training in all areas of conformal coating including conformal coating application techniques, conformal coating material selection, optimisation, conformal coating health & safety and trouble shooting conformal coating problems.